After you have done concentration meditation a bit you will notice how your attention (aka Awareness) moves. How it is constantly jumping and fixating on and reacting to this and that. A whole complex habitual dance. You will notice that.
So the technique of watching meditation goes like this :
Sit on your meditation pillow, back straight, breathing from your belly, eyes half-closed.
Watch everything (you can do this sitting or walking around, sitting is probably easier but whatever), the whole river of experience. All the sights, sounds, thoughts, feelings, etc. Watch all that stuff.
Watch, calm like in concentration but without concentrating on anything. Just watch. Watch the phenomena. Watch your attention. Watch how a phenomenon arises and falls, a sound or a thought or whatever. Watch how you react, how your attention reacts, to that sound, sight, thought, feeling.
Watch how you are invited to react to that sound or thought or whatever. To jump and fixate. To direct your attention here or there, at this or that.
And then, when presented with that invitation, decline it. Just keep your cool. Don't react. Just keep on watching.
That's it. That's the technique.
Do it. You'll like it.
NOTE#1 This technique is also called Insight, Shikantaza, Vipassana, Growing, Objectless, Formless, Untangling, Cessation and Asamprajnata Dhyana ( Meditation Without A Seed).
rewrite this better